Ok its not a Ford....sorry!!!! But, what is this? The car is a 1990 Golf GTI MK2. She has oil around 1 of the plugs. The rest are fine.

Pic of how it should look like all the other 3 plugs........




But this is what plug 4 looks like, and its not coming from rocker cover gasket, it seems to be coming out of where the plug lives!!!!!





What could it be, is it bad?